NWT RESEARCH DATABASE

Regions: Dehcho Region

Tags: physical sciences, ecology, carbon dioxide, methane, weather, permafrost thaw

Objective(s): To study the physical and chemical changes to the climate from permafrost thaw: to determine if carbon dioxide and methane changes differ in different permafrost zones if they respond to differences in amount of precipitation.

Project Description: This licence has been issued for the scientific research application No.5535. Through this project my research group will address the following objectives: What is the net effect of permafrost thawing induced biophysical and biogeochemical feedbacks to the climate system? How do these two types of feedback differ between the sporadic and discontinuous permafrost zones? Is the reported decrease (increase) in net carbon dioxide (methane) exchange based on plot- (<1m2) and ecosystem-scale (~1km2) flux measurements made over mostly tundra sites in the continuous permafrost zone generalizable to boreal forest and peatland ecosystems with sporadic and discontinuous permafrost? Do the net ecosystem carbon dioxude and methane exchanges of boreal forest and peatland ecosystems in different permafrost zones respond differently to higher/lower precipitation inputs than, for example, thawing/growing season lengths? Creek is a 15-m micrometeorological tower on which the eddy covariance system and supporting instrumentation will be installed. The eddy covariance system comprises a three-dimensional sonic anemometer to measure wind velocities, an open-path gas analyzer for carbon dioxide and water vapour concentrations and an open-path gas analyzer for methane concentrations. The covariance of the vertical wind velocities and the different concentrations will allow for the calculation of the respective fluxes between the landscape and the atmosphere. These quasi-continuous measurements are complemented by repeated surveys of surface and frost table topography, vegetation, micrometeorological and environmental conditions to understand the influence of spatial and temporal permafrost dynamics on vegetation composition and structure, by remote sensing-based footprint analysis to characterize landscape heterogeneity/homogeneity, and by continuous near-surface remote sensing to interpret eddy covariance measurements in a phenological framework. Based on my extensive network of contacts across the Northwest Territories, research results of my project will be presented informally in public meetings to local communities (e.g., we held a community outreach event in Wrigley in 2019) but also to local, federal and territorial government agencies. The fieldwork for this study will be conducted from: March 15 - September 05, 2023